Tokens

I had some questions about token usage in the game I ran last night:
(1) Can a PC use a token if they are assisting in a roll or do they need to be the PC making the roll?
(2) Can a PC obtain any type of token based on some activity, or is it limited to be one of the token types listed on their PC sheet?
(3) PCs sitting around for a day to gain tokens... is there something more proactive they can do to get these? (Probably depends on the answer to #2.)